When two societies which are only materially distinct from each other come into collision neither is to be sacrificed to placate the other, but the interests of each are to be catered for in a rigidly fair manner.
This principle is based on the fact that these two societies are of equal standing, enjoy therefore identical rights and have neither of them any legal advantage over the other; neither in fact is obliged to waive any of its rights in favour of the other. On this account a balance in no way derogatory to either must be struck as accurately as is possible between the conflicting rights; for example, by dividing up the disputed matter (granted it is divisible) or by making compensation. At times indeed the right claimed on one side may be a putative one only, and that on the other side clearly unimpeachable (objective); or at least one rather than the other side clearly unimpeachable (objective); or at least one rather than the other may have a greater interest at stake or stronger grounds on which to quarrel. But even in situations such as these, peaceful methods of settling the issue must take precedence over all others.
First of all, therefore, every effort should be made to establish the existence of whatever right is being claimed; then an attempt should be made to compose differences amicably; finally, should this fail, war must not be declared without first trying out certain coercive measures which, though of less consequence than war, may be equally effective in the circumstances. These last, indeed, are the only measures to be taken whenever it is clear that they of themselves can effect a settlement, and avoid the disasters of war.
But what of mediation, arbitration or an investigation by an international tribunal? Are not these also possible means? To me, indeed, they seem of so obligatory a nature that they alone are the only justifiable and lawful means of vindicating rights in present times; war is out of the question. It is important, however, to note with regard to this view that this is not the opinion of past centuries: in those days mediation, etc., were not considered the exclusive means of settling disputes between perfect or fully autonomous societies; they were at the most highly commendable from a humanitarian viewpoint. For, granting the concept of the sovereignty of every state, then each state, because of its very independence and perfection, was also possessed of the juridical power of safeguarding its rights even by force of arms. The state, it was held, had ample resources at its disposal with which to uphold its rights in face of an adversary struggling against or simply ignoring the obligations these rights imposed upon him.
Warfare, however, was not to be indulged in merely because one had a just and proportionate cause with which to justify the action; it also had to be necessary to the preservation of the social well-being, and withal reasonably assured of success.
The justification of war did not rest, therefore, on the presumption that war was as satisfactory as a duel between two private reasons: neither course proves on which side right and reason lie. No, the sole justification of recourse to warfare was on an occasion when there was little hope of appealing to, or - if a disputed right were in question - of getting a decision from an authority higher than the state. War could be used then to compel an adversary to make good some infringement of rights - but with the understanding that it was a physical instrument the only concern of which was to keep intact the moral implication of the right infringed.
All the foregoing reasoning is cogent enough if we confine ourselves to a purely theoretical treatment of warfare. But in practice and in relation to present conditions the principles enunciated do not seem to hold. They were meant, we should remember, to cover warfare of a special kind, that between mercenary armies, and not our mammoth warfare which sometimes entails the total downfall of the nations at grips with each other; the principles, in fact, cannot be applied in the life of modern nations without doing serious damage to the particular peoples involved, and (leaving aside a question of a defensive war begun, under certain conditions, for the protection of the state from actual and unjust aggression) no state is justified any longer in resorting to warfare when some right has not been given its full due. Not that we for a moment wish to despise or belittle the theories of the great exponents of Christian international law! That would be unpardonable! The war of their treatises is not the war of our experience. The difference indeed is not even of the purely numerical or mathematical order; it goes much deeper. It affects the very principles governing war. Principles indeed drive from and vary with the nature of things; the difference between war as it was and war as we know it is precisely one of nature.
At the Vatican Council the Fathers intimated to the Pope their desire that some definite statement be drawn up which might induce men to abandon warfare altogether or at least induce them to conduct their wars according to humanitarian principles. The salvation of certain Christian peoples was the chief cause of their concern; not simply because these peoples were then in the throes of war but "rather because of the horrible disaster" with which they were afflicted as a result of war. War, they were gravely troubled to note, was the occasion of disasters not the least of which, a lowering of moral standards, accompanied and persisted after war, and made shipwreck of the faith of so many souls. We in this century have even further cause for concern:
a. On account of the great development of communication in modern times and the desire on the part of nations to extend their interests to all parts of the world, excuses for war are now all too frequent.
b. The disasters which worried the Fathers at the Vatican Council now affect not only soldiers and armies at war but also entire peoples.
c. The extent of the damage done to national assets by aerial warfare, and the dreadful weapons that have been introduced of late, is so great that it leaves both vanquished and victor the poorer for years after.
d. Innocent people, too, are liable to great injury from the weapons in current use: hatred is on that account excited above measure; extremely harsh reprisals are provoked; wars result which flaunt every provision of the jus gentium, and are marked by a savagery greater than ever. And what of the period immediately after a war? Does not it also provide an obvious pointer to the enormous and irreparable damage which war, the breeding place of hate and hurt, must do to the morals and manners of nations?
e. In these days, when the world itself has become seemingly shrunken and straitened, the bonds between the nations of the world are so close and exigent that almost the whole world becomes involved once war is declared.
f. A regime may be under the impression that it can engage in a just war with hope of success; but in fact secret weapons can be prepared to such effect nowadays that they, being unforeseen, can upset and utterly thwart all calculations.
These considerations, and many others which might be adduced besides, show that modern wars can never fulfil those conditions which (as we stated earlier on in this essay) govern - theoretically - a just and lawful war. Moreover, no conceivable cause could ever be sufficient justification for the evils, the slaughter, the destruction, the moral and religious upheavals which war today entails.
In practice, then, a declaration of war will never be justifiable. A defensive war even should never be undertaken unless a legitimate authority, with whom the decision rests, shall have both certainty of success and very solid proofs that the good accruing to the nation from the war will more than outweigh the untold evils which it will bring on the nation itself, and on the world in general.
Otherwise the government of peoples would be no better than the reign of universal disaster, which, as the recent war has shown, will claim its victims more from the civilian population than from the combatant troops. In what way then shall international crises be dealt with on future occasions? "Discussion and force", says Cicero, "are the main ways of settling quarrels, the former of which is peculiar to man, the latter to brute beasts". The former therefore is ever to be preferred; the interests of peace must be our chief concern ever - and it is not the forming of armies but the formation of minds which will best secure this.
In this formation the weapons of charity, justice and truth shall be:
a. A civil and religious education of nations which so disposes peoples (and hence the rulers chosen from them) to co-operation and to an honourable recognition and interchange of rights and obligations, that class bitterness, race enmity and imperial competition - than which there is no better kindling for wars - are entirely eliminated.
b. The setting up of an international body whose pronouncements all nations and rules should respect.
c. The inculcation among peoples of a spirit of brotherliness in accord with gospel principles; as a result each nation will be prepared to place the good of the whole human brotherhood before its own interests, in the manner in which individuals in any republic worthy of the name ought always to contribute to the common good from whatever they themselves possess.
d. To render impossible totalitarian regimes, for they above all else are the turbulent sources from which wars break out. Moreover, should the representatives of any people (or the people themselves) ever have conclusive indications that their rulers are on the point of undertaking a war in which nothing but blood and ruin will be the lot of the nation, they should and ought to take just measures to overthrow that regime.
Card. Alfredo Ottaviani, Institutiones Juris Publici Ecclesiastici, Vol. 1 (Jus Publicum Internum) Pars I, Titulus iii, art. 3 (Relationes societatum perfectarum in statu conflictus) Principium 2 - Vatican, Polyglot. 3rd Edition (1947) pp. 149-55
English translation: Blackfriars - a monthly review. Edited by the English Dominicans. Published at Blackfriars, St Giles, Oxford, Vol. XXX September 1949 No. 354